In recent years, the use of communication systems having wireless mobile communication units which communicate using an optical or radio link with a hardwired network, such as a local area network (LAN), has become quite widespread. Retail stores and warehouses, for example, may use such systems to track inventory and replenish stock. Employees may enter inventory information using a hand held or portable communication unit which can be carried through the store or warehouse. In manufacturing facilities, such systems are useful for tracking parts, completed products and defects. In a medical environment, these systems can reduce the time needed to fill out forms and eliminate inaccuracies by allowing medical personnel to transmit data directly from a mobile communication unit carried by the medical personnel.
A conventional communication system generally includes a number of fixed base stations (i.e., access points) interconnected by a cable medium to form a hardwired backbone network. The network medium may be a twisted pair cable, shielded coaxial cable for fiber optic lines, for example. Each base station has a service area or cell surrounding the base station within which it has the ability to transmit and to receive relatively error-free data from a mobile communication unit within the area.
In such a network, a mobile communication unit must initially register itself with a base station and then attempt to begin a session with a host computer whereby the host allows communication to occur between itself and the particular mobile communication unit. More particularly, when a mobile communication unit is powered up, it "registers" with a base station. However, as the location of this mobile communication unit changes, the mobile communication unit may register with another base station, thereby resulting in a deregistration with the previous base station. Furthermore, deregistration will sometimes occur if there is no communication between the mobile communication unit and its corresponding base station within a predetermined period of time. Thus, in such communication systems, mobile communication units register and deregister frequently as the mobile communication units are moved about.
As mentioned above, each mobile communication unit within the communication system must also begin and maintain a session with the host computer (or other device which provides application or information based services) once it has registered with a base station. A session is typically only initiated once at start up by each mobile communication unit and is active until such time as the mobile communication unit ends the session regardless of the number of registrations and deregistrations which may have taken place with respect to base stations during this period. In order for the mobile communication unit to enter into the system and begin a session with the host computer, the mobile communication unit must have a unique system identification code (ID). The ID allows the host computer or other device on the backbone handling session requests to recognize and distinguish each mobile communication unit.
Mobile communication units which do not come equipped with hardware which preassigns a unique address (such as a medium access control (MAC) address) must handle addressing via software. Typically, for example, upon shipping one or more mobile communication units to a location for interfacing with a network communication system a programmer at the location would individually program each mobile communication unit with a unique system ID. The mobile communication units cannot be preprogrammed with the system ID because it is possible that the system in which the mobile communication units are about to be used are already supporting other mobile communication units and care must be taken to ensure that duplicate device ID's are not granted.
Unfortunately, the process of individually programming each mobile communication unit requires that trained personnel be on site to complete the programming and physically handle each mobile communication unit to perform the necessary initialization steps. This of course often results in significant delay times from the time shipment of the product is received to when such mobile communication units can actually communicate within the network system. Furthermore, such location based programming efforts can be substantially costly.
Accordingly, there is a strong need in the art for a system and method which eliminates the need to individually, manually program mobile communication units with a unique system ID so that the mobile communication units can properly communicate in a network communication system. In particular, there is a strong need in the art for an ID assignment system which detects a mobile communication unit which is attempting to access a communication system (i.e., with a session request or base station registration process) without a valid ID or any ID at all, and which assigns a valid ID to the mobile communication unit so that the mobile communication unit may access the network system.